A Case of Amantadine-Induced Corneal Edema

Purpose: To report a rare case of corneal edema caused by amantadine. Case summary: A 35-year-old man was diagnosed with hypoxic brain damage caused by ventricular fibrillation. The patient showed Parkinsonism and was started on treatment with amantadine. Thirty-seven months after the commencement of amantadine treatment, the patient suffered a corneal ulcer in his right eye, which healed with opacity and thinning after medical treatment. After healing, slit-lamp examination revealed a bilateral, epithelial and stromal edema without obvious guttae and keratic precipitates. The corneal edema did not improve with topical treatment of 5% NaCl and 0.02% fluorometholone in both eyes. Three months after leaving the hospital, the patient’s corrected visual acuity decreased to 0.2 (-2.0 Dsph -0.5 Dcyl Ax 90) in the right eye and 0.4 (-0.75 Dsph -2.0 Dcyl Ax 90) in the left eye. Amantadine medication was discontinued after discussion with the patient’s neurologist. At the 1-month follow-up, corneal examination revealed resolution of the epithelial and stromal edema in both eyes. Corrected visual acuity was improved to 0.5 (-1.5 Dsph) in the right eye and 0.7 (-1.0 Dsph -1.0 Dcyl Ax 90) in the left eye. Conclusions: In cases of corneal edema without an obvious causative disease, the patient’s systemic medication list must be reviewed and amantadine should be considered as a possible cause.